SyntaxHighlighter 3.0.83

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SyntaxHighlighter is an open source Java Script client side code syntax highlighter.
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Scala Example

      package examples

      /** Illustrate the use of pattern matching in Scala.
       *  Like patterns.scala, but uses extractors for representation independence
      object extractorPatterns {

        /** We need an abstract base class for trees. Subclasses with
         *  the 'case' modifier can be used in pattern matching expressions
         *  to deconstruct trees.
         *  Here, we replaced case classes of patterns.scala with objects
         *  that hide the actual implementation of Branch and Leaf. Note
         *  that the remaining code does not change. In this way, we
         *  can change the implementation later without affecting clients,
         *  which is called representation independence.
        abstract class Tree

        object Branch {
          /* method to contruct branches @see extractorPatterns.tree1 */
          def apply(left: Tree, right: Tree): Tree = new BranchImpl(left, right)
          /* extractor method referenced in match expressions @see extractorPatterns.sumLeaves */
          def unapply(x:Tree): Option[(Tree,Tree)] = x match {
            case y:BranchImpl => Some(y.left, y.right)
            case _            => None
          private class BranchImpl(val left:Tree, val right:Tree) extends Tree
        object Leaf {
          /* method to contruct leaves @see tree1 */
          def apply(x:Int): Tree = new LeafImpl(x);
          /* extractor method referenced in match expressions @see extractorPatterns.sumLeaves */
          def unapply(x:Tree): Option[Int] = x match {
            case y:LeafImpl => Some(y.x)
            case _          => None
          private class LeafImpl(val x: Int) extends Tree

        /** Case classes have an implicit constructor methods which allows
         *  to create objects withouth the 'new' keyword. It saves some typing
         *  and makes code clearer.
         *  Here, the task of the case class constructor is performed by the
         *  method Branch.apply - the singleton Branch is treated as if it
         *  were a function value. This trick works with any value that has
         *  an apply method.
        val tree1 = Branch(Branch(Leaf(1), Leaf(2)), Branch(Leaf(3), Leaf(4)))

        /** Return the sum of numbers found in leaves.
         *  'match' is a generalization of 'switch' in C-like languages
         *  Patterns consist of case class constructors (which can
         *  be nested), and lower case variables which are
         *  bound to the values with which the class has been constructed.
         *  For extractors, it is not the name of a case class, but the name of
         *  the singleton object Branch which is used to refer to its extractor method
         *  Branch.unapply - the pattern is the 'reverse' of a method
         *  call, with the result being matched in the subpatterns. This works
         *  for any value that has an appropriate extractor method.
        def sumLeaves(t: Tree): Int = t match {
          case Branch(l, r) => sumLeaves(l) + sumLeaves(r)
          case Leaf(x) => x

        /** This illustrates the use of Option types. Since the
         *  method is not known in advance to find 'x', the
         *  return type is an Option. Options have two possible
         *  values, either 'Some' or 'None'. It is a type-safe
         *  way around 'null' values.
        def find[A, B](it: Iterator[Pair[A, B]], x: A): Option[B] = {
          var result: Option[B] = None
          while (it.hasNext && result == None) {
            val Pair(x1, y) =;
            if (x == x1) result = Some(y)

        def printFinds[A](xs: List[Pair[A, String]], x: A) =
          find(xs.elements, x) match {
            case Some(y) => println(y)
            case None => println("no match")

        def main(args: Array[String]) {
          println("sum of leafs=" + sumLeaves(tree1));
          printFinds(List(Pair(3, "three"), Pair(4, "four")), 4)
Brush nameBrush aliasesFile name
ActionScript3as3, actionscript3shBrushAS3.js
Bash/shellbash, shellshBrushBash.js
ColdFusioncf, coldfusionshBrushColdFusion.js
C#c-sharp, csharpshBrushCSharp.js
C++cpp, cshBrushCpp.js
Delphidelphi, pas, pascalshBrushDelphi.js
Diffdiff, patchshBrushDiff.js
Erlangerl, erlangshBrushErlang.js
JavaScriptjs, jscript, javascriptshBrushJScript.js
JavaFXjfx, javafxshBrushJavaFX.js
Perlperl, plshBrushPerl.js
Plain Textplain, textshBrushPlain.js
PowerShellps, powershellshBrushPowerShell.js
Pythonpy, pythonshBrushPython.js
Rubyrails, ror, rubyshBrushRuby.js
Visual Basicvb, vbnetshBrushVb.js
XMLxml, xhtml, xslt, html, xhtmlshBrushXml.js